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I went to <a href=" http://www.disruptivematerials.com/buying-xenical.pdf ">where to buy xenical in singapore</a> Like other atomic clocks, the new ytterbium clocks rely upon cooling atoms down to near absolute zero. The atoms, frozen to just 10 millionths of a degree above absolute zero, are suspended in an optical lattice framework. A laser that "ticks" 518 trillion times per second provokes a measurable transition between energy levels in the atoms, of which there are about 10,000. The large number of atoms is key to the clocks' high stability, the NIST said.
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